In industrial production processes such as machining, metal cutting, rolling, forging, etc., a large amount of cutting oil, lubricating oil, or coolant is used. High speed equipment will atomize these oils, forming tiny droplets suspended in the air - known as "oil mist". Long term exposure to high concentrations of oil mist not only irritates the eyes, skin, and respiratory tract of operators, but may also cause chronic bronchitis, asthma, and even increase the risk of cancer. In addition, oil mist deposition can also pollute the workshop environment, reduce equipment insulation performance, and affect product quality. In order to scientifically evaluate the concentration of oil mist in workplaces, oil mist testers have emerged and become important technical equipment for occupational health protection and safety production supervision.
An oil mist tester is a portable or fixed detection device specifically designed to collect and measure the mass concentration of inhalable oil mist particles in the air. Its working principle is usually based on membrane weighing method or light scattering/photometry method. In standard methods such as GBZ/T 160.38-2007, NIOSH 5521, OSHA Method 24, membrane sampling combined with laboratory weighing is commonly used: a certain volume of oil mist air is pumped through a specially designed glass fiber or polytetrafluoroethylene (PTFE) membrane by an air pump, and the oil mist is intercepted. The difference in membrane mass before and after sampling divided by the gas collection volume can calculate the oil mist concentration (unit: mg/m ³). This method has high accuracy and is the "gold standard" for arbitration and compliance testing.
On site rapid screening often uses light scattering oil mist testers. This type of instrument is equipped with a laser light source and a photodetector. When oil mist particles pass through the beam, scattered light is generated, and its intensity is proportional to the particle concentration. After calibration, the oil mist concentration value can be displayed in real time, with a fast response speed (in seconds) and easy operation, suitable for workshop inspection, ventilation system efficiency evaluation, and emergency monitoring.
Modern oil mist testers focus on practicality and safety in their design. The equipment is usually explosion-proof, oil proof, and the shell is sturdy and durable; Stable sampling flow rate (such as 2 L/min), built-in flow calibration function; Partially integrated temperature and humidity sensors automatically compensate for the impact of environmental factors on measurement. For different oil products (mineral oil, synthetic ester, water-based emulsion, etc.), manufacturers provide dedicated calibration curves to improve measurement accuracy.
In practical applications, oil mist testers are widely used in high-risk industries such as automotive manufacturing, aerospace, mold processing, and bearing factories. Enterprises can conduct regular inspections to determine the effectiveness of local exhaust devices (such as oil mist collectors), optimize process parameters (such as reducing cutting speed and using low atomization coolant), and provide a basis for equipping employees with appropriate respiratory protective equipment. At the same time, the environmental protection and safety supervision departments have also included oil mist concentration in occupational health supervision and inspection indicators, promoting the implementation of the "Healthy China" strategy on the front line of industry.
It is worth noting that the composition of oil mist is complex and may contain carcinogens such as polycyclic aromatic hydrocarbons (PAHs), so measuring only the total oil mist concentration is sometimes insufficient. In high-risk scenarios, it is necessary to combine chemical analysis (such as GC-MS) for component identification. In addition, the height of the worker's breathing belt (about 1.5 meters) should be selected during sampling to avoid dead corners of the airflow and ensure data representativeness.
In short, although the oil mist tester is compact, it carries the significant mission of safeguarding the respiratory health of workers. It transforms invisible air pollution into quantifiable and manageable data, and is a key tool for implementing the "prevention first, prevention and control combined" occupational disease prevention and control policy. In the wave of intelligent manufacturing and green factory construction, this equipment is not only required for compliance, but also a reflection of corporate humanistic care and sustainable development.